Реферат на тему Animal Chromosomes Essay Research Paper Different kinds
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Animal Chromosomes Essay, Research Paper
Different kinds of Animal chromosomes exist with very different parts. To start, in animal cells three different kinds of chromosomes can be seen. The first kind is the X chromosome, which is one of the sex-determining chromosomes. The other sex-determining chromosome is the Y chromosome. The rest of the chromosomes are referred to as autosomes. Two different kinds of animal cells exist, male and female, each of which has a different make up of chromosomes. For example, the male fruit fly has 3 pairs of autosomes and one pair of sex-determining chromosomes made up of an X chromosome and a Y chromosome, while the female has 3 pairs of autosomes and one pair of sex-determining chromosomes made up of two X chromosomes. Moving on, when each chromosome doubles to ensure genetic information is passed on to a new cell the chromosome becomes two strands. These strands are called chromatids and are connected at a point by a centromere. The centromere is where the chromosomes separate when they are ready to move to new cells. In summation several kinds of animal chromosomes exist with different parts.
Several different components exist in a chromosomes physical nature. To start, when chromosomes first forms from the material inside the nucleus the texture is very rough and the chromosomes are very incomplete with seeming wholes and gaps in them. In the next the few stages the chromosomes become smoother with no rough edges or gaps. To continue, after the chromosome first forms it develops into chromatids as explained above. These chromatids are attached at the very bottom by a centromere. When the chromosomes become complete sets the centromere moves closer to the middle of the two chromosomes. While all this has been going on the individual chromosomes have maintained some sort of rod shape. Also, the individual chromosomes contain genetic traits such as eye color. These traits can be mapped out in chromosomes mapping where each trait’s position is pinpointed on the individual chromosome.